<!--
 * @Description: 
 * @Version: 2.0
 * @Author: godless
 * @Date: 2024-06-28 23:20:55
 * @LastEditors: godless
 * @LastEditTime: 2024-06-29 19:50:39
-->
<template>
  <el-breadcrumb class="app-breadcrumb" separator="/">
    <transition-group name="breadcrumb">
      <el-breadcrumb-item v-for="(item, index) in levelList" :key="item.path">
        <span
          v-if="item.redirect === 'noRedirect' || index == levelList.length - 1"
          class="no-redirect">
          {{ item.meta.title }}
        </span>
        <!-- .prevent: 阻止 <a> 标签的默认跳转行为-->
        <a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script>
import pathToRegexp from "path-to-regexp";
export default {
  name: "Breadcrumb",
  data() {
    return {
      levelList: null,
    };
  },
  created() {
    this.getBreadcrumb();
  },
  watch: {
    $route() {
      this.getBreadcrumb();
    },
  },
  methods: {
    getBreadcrumb() {
      // console.log(this.$route);
      // console.log(this.$route.matched); // 数组
      //一个数组，包含当前路由的所有嵌套路径片段的路由记录 。路由记录就是 routes 配置数组中的对象副本 (还有在 children 数组)。
      let matched = this.$route.matched.filter((item) => {
        // console.log(item);
        return item.meta && item.meta.title;
      });
      // console.log(matched);

      const first = matched[0];

      if (!this.isHome(first)) {
        matched = [{ path: "/home", meta: { title: "首页" } }].concat(matched);
      }

      this.levelList = matched.filter((item) => item.meta && item.meta.title);
      // console.log(this.levelList, "this.levelList");
    },
    isHome(route) {
      const name = route && route.name;
      if (!name) {
        return false;
      }
      return name.trim().toLocaleLowerCase() === "Home".toLocaleLowerCase();
    },
    pathCompile(path) {
      // To solve this problem https://github.com/PanJiaChen/vue-element-admin/issues/561
      const { params } = this.$route;
      let toPath = pathToRegexp.compile(path);
      return toPath(params);
    },
    handleLink(item) {
      const { redirect, path } = item;

      if (redirect) {
        this.$router.push(redirect);
        return;
      }

      this.$router.push(this.pathCompile(path));
    },
  },
};
</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb {
  display: inline-block;
  font-size: 14px;
  line-height: 50px;
  margin-left: 8px;

  .no-redirect {
    color: #97a8be;
    cursor: text;
  }
}
</style>
